Apparatus and methods for operating devices in wellbores using signal transmitters in a drop device

ABSTRACT

An apparatus for operating a device in a wellbore is disclosed that in one non-limiting embodiment includes a drop device configured to be dropped into the wellbore that transmits a selected signal while the drop device is traveling in the wellbore, a control circuit in the wellbore that detects the transmitted selected signal and provides a control signal in response to the detected signal to operate the device in the wellbore.

BACKGROUND 1. Field of the Disclosure

This disclosure relates generally to apparatus and methods for operating devices in wellbores using signal transmission by a transmitter in a drop device.

2. Background of the Art

Wellbores are formed in subsurface formations for the production of hydrocarbons (oil and gas). Modern wells descend to great well depths, often more than 15,000 ft. Hydrocarbons are generally trapped in zones at various depths. A variety of sensors and tools are used to determine the location of such zones. A drilled wellbore at such a stage is referred to as open hole. To recover hydrocarbons, the wellbore is typically lined with a casing (serially connected metal tubulars) along the length of the wellbore to prevent collapse of the formation (rocks) into the wellbore. Such a wellbore is referred to as a cased wellbore. The zones bearing hydrocarbons are perforated through the casing to cause the hydrocarbons to flow from such zones to within of the casing. A string, such a work string or a completion string, containing a variety of devices or tools, is installed inside the casing or the open hole to controllably allow fluid containing hydrocarbons to move from the formation into the wellbore and to transport such fluid to the surface. The equipment on such as string is often referred to as the completion equipment. The completion equipment includes a variety of tools and devices, which may be electrically, hydraulically, electrically and/or mechanically operated, i.e. activated and/or deactivated to perform a variety of intended functions. Often a service string is conveyed into the completion string to operate devices in the work string. Service strings carrying a transmitter that transmits signals, such as light signals, in the wellbore to operate certain devices have been proposed. In one such system, a light source is mounted on a string to transfer data from sensors and memory located at the surface to a downhole device. Another system proposes a method of activating downhole tools using light signals transmitted via fiber-optic cables run inside a service string conveyed into the wellbore. Such systems require conveying a string in the wellbore or installation of communication links in the completion strings for operating various devices, which are very expensive and time consuming.

The disclosure herein provides apparatus and methods in which control signals or selected signals are generated in a wellbore by a transmitter carried by device traveling through the wellbore to operate one or more downhole devices.

SUMMARY

In one aspect, an apparatus for operating a device in a wellbore is disclosed that in one non-limiting embodiment includes a drop device configured to be dropped into the wellbore that transmits a selected signal while the drop device is traveling in the wellbore, a control circuit in the wellbore that detects the transmitted selected signal and provides a control signal in response to the detected signal to operate the device in the wellbore.

In another aspect, a method of operating a device in a wellbore is disclosed that in one non-limiting embodiment includes: dropping a drop device in the wellbore that transmits a selected signal while the device is traveling in the wellbore; detecting by a detector in the wellbore the transmitted signal; and operating the device in the wellbore in response to the detected signal.

Examples of the more important features of certain embodiments and methods according to this disclosure have been summarized rather broadly in order that the detailed description thereof that follows may be better understood, and in order that the contributions to the art may be appreciated. There are, of course, additional features that will be described hereinafter and which will form the subject of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a detailed understanding of the apparatus and methods disclosed herein, reference should be made to the accompanying drawing and the detailed description thereof, wherein:

FIG. 1 shows a line diagram of a wellbore system that includes a device desired to be operated utilizing a control signal transmitted by a drop device traveling in the wellbore; and

FIG. 2 shows an exemplary drop device that includes a number of transmitters configured to transmit omnibus control signals.

DETAILED DESCRIPTION

In general, the disclosure herein provides apparatus and methods for operating (activating and/or deactivating) devices (also referred to herein as the target device or devices) disposed in a wellbore using signals such as light signals, acoustic signals and electromagnetic signals, without the use of strings conveyed into the wellbore or via links disposed or installed in the wellbore, such as conductors or fiber optic links. In one non-limiting embodiment, the apparatus includes a drop device, such as a drop ball, that is dropped from a surface location or from a tool located up hole from the device to be operated. The drop device may contain one or more transmitters or sources that transmit certain selected signals while the drop device is traveling in the wellbore. In one embodiment, a transmitter may include a light source, such as light emitting diodes (LEDs), an electromagnetic signal generator, an acoustic source, or another suitable signal generator. The transmitted signals may include one or more signals selected from a range of signals, such as signals having different frequencies, wavelength, etc. The apparatus may include a control circuit or control unit configured to detect the transmitted signals and provide one or more control signals to operate one or more target devices. A power unit may operate an associated device to be operated in response to the one or more control signals. In one embodiment, the control circuit includes a detector configured to detect the selected signals transmitted by the drop device. In the case of light signals, the receiver may include photodetectors to receive the transmitted light signals. A controller, such as a micro-processor based circuit, in the control circuit may be configured to process certain selected signals detected by the detector, such as signals corresponding to certain frequencies, and generate control signals to operate selected devices. In one non-limiting embodiment, when the drop device is proximate to or passes by the device to be operated, the detector in the control circuit detects or senses the transmitted signal that corresponds to or relates to its associated device to be operated and provides a control signal to a power unit associated with such device to operate the device. The controller in the control circuit may be programmed to generate the control signals to operate specific devices in response to the transmitted signals. A single drop device may be utilized to transmit a variety of signals to operate more than one device in the wellbore. Also, a common control circuit may be utilized to provide specific control signals (for example, signals having different wavelength or frequency for each device) corresponding to more than one device, or a separate receiver may be utilized for each device to be operated. In such cases, the drop device generates a specific signal for each device to be operated and the common receiver or separate receivers, as the case may be, provide corresponding control signals. In another embodiment, the same downhole device may be configured to perform different functions in response to different signals transmitted by the drop device. In the apparatus and methods described herein, the drop device does not need to contact a target device in order to convey the transmitted signal to its associated detector. Thus, the drop device may be sized to pass through the device to be operated without blocking the internal diameter of such a device. Also, in the case of light signals, the emitted light may be visible light or it may extend to other wavelengths on the electromagnetic spectrum, such as ultraviolet light or infrared light.

FIG. 1 shows a wellbore system 100 that includes a wellbore 101 formed in a formation 102 that is lined with a casing 104. The annular space 105 between the wellbore 101 and the casing 104 is shown filled with cement 106. An exemplary work string 110 is shown conveyed inside the casing 104. In one-non limiting embodiment, the work string 110 may a completion string for producing hydrocarbons (oil and gas) from one or more production zones (not shown) in the formation 102. A work string may include a number of devices, including, but not limited to, packers, sliding sleeves or other type of valves, mechanical devices, hydro-mechanical devices, and electro-mechanical devices that are operated (activated and/or deactivated) downhole to perform one or more selected functions or operations. The apparatus for operating devices disclosed herein may be configured to operate any suitable device in the wellbore. For illustration purpose and for ease of understanding, the work string 110 is shown to include a through passage 112 and a tool or apparatus 120 positioned at a location 110 a that includes a device 122 desired to be operated. The tool 120 is further shown to include a control circuit or control unit 130 and a power unit 124 associated with the device 122. The device 122 is configured to be activated and/or deactivated by the power unit 124 in response to a control signal received from the control circuit 130. The power unit 124 may be a hydraulic device, a mechanical device, an electrical device or any combination thereof. For purpose of explanation and not as a limitation, the device 122 is shown as an anchor, wherein activating the device 122 means causing a member 122 a thereof to extend from a retracted position to an extended position to contact the casing 104. If the device to be operated is a valve, such as a sliding sleeve valve, or solenoid valve, activating such a device means opening the valve and deactivating the device means closing the valve. The control circuit 130 controls the operation of the device 122 in response to detection of one or more selected signals from a device traveling through the wellbore, such as a drop device, as described later. in one non-limiting embodiment the control circuit 130 may include a detector or receiver 132 that is configured to detect one or more selected signals, a controller 134 that processes the signals detected by the detector 132 and provides one or more control signals in response to the detected signals to the power unit 124 to operate the device 122. The controller 134 may include analog and/digital circuits known in the art and may include a microprocessor for processing the detected signals and for generating control signals. A power unit 136, such as a battery may be provided to provide electrical energy to the various components of the control circuit 130.

Still referring to FIG. 1, the apparatus described herein may be utilized to operate multiple devices in the wellbore. As an example, the work string 110 may further include a second tool or apparatus 160 that includes a device 150 to be operated. The exemplary device 150 is a control valve device that is shown to include valves 150 a, 150 b and 150 c for controlling flow of a fluid 115 through the work string passage 112. In the particular exemplary device 150, when the valves 150 a and 150 b are closed and the valve 150 c is open, the fluid 115 will flow through the passage 112. When the valve 150 c is closed and valves 150 a and 150 b are open, fluid 115 will flow through the annular space 170 between the casing 104 and the work string 110. Therefore, in such a configuration, selectively operating the valves 150 a, 150 b and 150 c allows controlling flow of fluid 115 though the wellbore system 100. Also, in one embodiment, the control circuit 130 may be common to both devices 122 and 150 while in another embodiment, each such device may include a separate control circuit. In the case of a common control circuit, such as control circuit 130, a communication link, such as link 135, may be provided in the work string 110 between the control circuit 130 and the device 150 to provide control signals to a power unit 165 to operate the device 150. In the case of separate control circuits, another control circuit 180, similar to control circuit 130, may be provided for device 150.

FIG. 2, shows an exemplary drop device 200, which in one non-limiting embodiment may be a ball that includes one or more transmitters, transmitters 202 a-202 n, that are configured to generate selected signals in the wellbore corresponding to one or more target devices. In the case of light signals, the transmitters 202 a-202 n transmit light at one or more frequencies or wavelengths within a range of frequencies or wavelengths. In one non-limiting embodiment, the transmitters 202 a-202 n may be placed around the device to transmit omnidirectional selected light signals (i.e. 360 degrees around the device). Referring now to FIGS. 1 and 2, to operate a device in the wellbore system 100, such as device 122 and/or 150, the device 200 is dropped from the surface or from a location above the device 150 into the work string 110. The transmitters 202 a-202 n transmit signals that are specific to operating devices 120 and 150. while the device is traveling through the string 110. In the case of a common control circuit 130, the detector 132 detects the selected transmitted signals and the controller 134 sends separate control signals to each of the devices 120 and 150. In the case of separate control circuits, for example control circuit 130 for device 120 and control circuit 180 for device 150, each such control circuit is configured to detect signals that are specific to its associated device or devices and to generate corresponding control signals for operating such associated devices.

Thus, in aspects, to operate a device such as device 122, the drop device 200 is dropped from a surface location or a location in the wellbore above the device 122 into the work string 110, wherein the transmitters 202 a-202 n transmit control signals specific for device 122. The detector 132 detects such signals and the controller 134 sends control signals to the power unit 124 to cause it to operate the device 122. If another device, such as device 150, is also to be operated, the transmitters 202 a-202 n are configured to transmit signals corresponding to both devices 122 and 150. The control circuits 130 and/or 180, as the case may be, detect the signals corresponding to their associated device and send control signals to operate device 122 and device 150. In this manner, multiple devices may be operated or controlled by using a single drop device. The controllers in the control circuits 130 and/or 180 may be programmed to send control signals that are timed in a manner so as to operate various devices in any desired sequence and at any desired time. In this manner, a single drop device may be utilized to operate multiple devices in any desired sequence at any desired time regardless of their location (depth) in the wellbore.

The foregoing disclosure is directed to the certain exemplary embodiments and methods of apparatus and method for operating one or more devices in a wellbore. Various modifications to the apparatus and methods disclosed herein will be apparent to those skilled in the art. It is intended that all such modifications within the scope of the appended claims be embraced by the foregoing disclosure. The words “comprising” and “comprises” as used in the claims are to be interpreted to mean “including, but not limited to.” Also, the abstract is not to be used to limit the scope of the claims. 

1. An apparatus for operating a device in a wellbore, comprising: a drop ball configured to travel in the wellbore, the drop ball including a plurality of light emitting diodes arranged on the drop ball to transmit a selected omnidirectional light signal while the drop ball is traveling in the wellbore; and a control circuit configured to detect the selected light signal as the drop ball passes the control circuit and provide a control signal to the device in response to the detected selected light signal to operate the device in the wellbore.
 2. (canceled)
 3. The apparatus of claim 1, wherein the control circuit includes a light detector configured to detect the transmitted light signal
 4. The apparatus of claim 1, wherein the control circuit includes a controller that processes the detected signal and provides the control signal in response to the detected signal.
 5. The apparatus of claim 1, wherein the selected signal transmitted includes a plurality of signals, each such signal configured to operate a different device in the wellbore.
 6. The apparatus of claim 5 further comprising a power unit that operates the device in response to the control signal, and wherein the power unit includes a device selected from a group consisting of: an electrical device; a hydraulic device; a mechanical device; and a combination thereof.
 7. (canceled)
 8. The apparatus of claim 1, wherein the device is selected from a group consisting of: a flow control device; a packer; an anchor; and a fishing device.
 9. The apparatus of claim 1, wherein the wellbore includes a string containing the device to be operated and at least one restriction and wherein the drop ball is configured to pass through the at least one restriction in the string.
 10. (canceled)
 11. A method of operating a device in a wellbore, the method comprising: transmitting a selected omnidirectional light signal in a wellbore by drop ball traveling in the wellbore, wherein the drop ball includes a plurality of light emitting diodes disposed on the drop ball to transmit the omnidirectional light signal as the drop ball is traveling in the wellbore; detecting the transmitted selected light signal at a control circuit at a selected location in the wellbore as the drop ball passes the control circuit; providing a control signal from the control circuit to the device in response to the detected selected light signal; and operating the device in response to the control signal.
 12. (canceled)
 13. The method of claim 11, wherein the detecting the selected signals includes detecting such signal by a light detector in the wellbore.
 14. The method of claim 11, wherein transmitting a selected signal comprises transmitting a plurality of signals.
 15. The method of claim 14, wherein each signal in the plurality of signals is configured to operate a different device in the wellbore.
 16. The method of claim 11, wherein operating the device in response to the control signal comprises operating the device that is one of: an electric device; a hydraulic device; a mechanical device; and a combination of two or more of the electrical device, hydraulic device and mechanical device.
 17. (canceled)
 18. The method of claim 11, wherein the device is selected from a group consisting of: a flow control device; a packer; an anchor; and a fishing device.
 19. The method of claim 11, wherein the device is disposed in a string placed in the wellbore and wherein the string includes a restriction and wherein the drop device is configured to pass through the restriction in the string.
 20. (canceled)
 21. The apparatus of claim 1, wherein the drop ball transmits signals as the drop ball is traveling through a location in the wellbore above the control circuit, and the control circuit detects the selected light signal as the drop ball passes the control circuit. 